Memory mirror system for vehicles

ABSTRACT

A vehicle memory mirror system includes a vehicle mirror assembly and a control module. The vehicle mirror assembly includes a reflective element, a motor for positioning the reflective element about an axis, a monitor for monitoring the position of the reflective element with respect to the axis, and a mirror-based control including a position control which is operatively connected with the motor and the monitor in order to position the reflective element at a particular position. The control module is interconnected with the mirror-based control by an analog interface and includes a processor for providing analog signals on the analog interface indicative of a desired position of the reflective element with respect to the axis. The mirror-based control preferably includes a servo-amplifier circuit. The control module can control the speed of movement by formatting a series of sequential signals on the interface, each representing an incremental movement of the reflective element.

This application is a continuation of application Ser. No. 09/448,690,filed Nov. 24, 1999, which is a continuation of application Ser. No.09/135,375, filed Aug. 17, 1998, now U.S. Pat. No. 6,093,976, which is acontinuation of application Ser. No. 08/818,918, filed Mar. 17, 1997,now U.S. Pat. No. 5,796,176, which is a continuation-in-part ofapplication Ser. No. 08/679,681 filed Jul. 11, 1996, now U.S. Pat. No.5,798,575.

BACKGROUND OF THE INVENTION

This invention relates generally to vehicle rearview mirror systems and,more particularly, to vehicle memory mirror systems.

Vehicle memory mirror systems include at least one, and preferably two,electrically operated motors, each of which positions the reflectiveelement with respect to a given axis. By positioning the reflectiveelement about two generally perpendicular axes, the plane of the mirrorcan be fully positioned. A user-operable switch, such as a joystick orswitch pod, is useful to automatically position the mirrors. In a memorymirror system, a monitor device, such as a potentiometer which iscoupled to the reflective element, produces a signal indicative of theposition of the reflective element with respect to each axis ofmovement. The signal produced by the monitor device is used in aclosed-loop control to allow a controller to reliably position themirror to particular positions. In this manner, positions of the mirrorfor different drivers can be stored in memory and retrieved in order toset the mirrors for that driver.

It is generally known in vehicle control systems to providecommunication between a vehicle control module and one or moreperipheral devices by various communication techniques including digitalcommunications, pulse-width modulation, or other analog communications.It is also generally known to apply such communication techniquesbetween a vehicle control module and control modules in each of theexterior mirror assemblies of the vehicle.

A vehicle typically includes at least two mirrors mounted external ofthe vehicle, both of which are controlled in the same fashion. In orderto avoid duplication of hardware, it is common to provide oneuser-operable input device in order to control both mirrors. That devicetypically includes manual buttons for manually positioning the mirror, aselector switch to select one of a driver said or a passenger saidmirror; and memory set and recall buttons for operating the memoryfeatures of the mirror. The user-operable input device is typicallyassociated with a control device in order to multiplex the switchesmaking up the user-operable device and to communicate with each of thereflective elements. In order to reduce the number of wires between thecontrol device and each of the mirrors, various techniques have beenproposed to multiplex the signals. One such technique is to provide abidirectional digital communication link between each of the outsidemirrors and a central vehicle-based control. The central vehicle-basedcontrol receives switch inputs from the user-operable device. Thecentral control provides digitally encoded commands to each of themirrors. A control in each of the mirrors includes a memory element inorder to store particular mirror settings entered by one or more vehicleoperators, a data processor, and a position sensor for the reflectiveelement. The data processor compares feedback signals from the positionsensor in order to position the reflective element to a position storedin the memory element. In this manner, the central vehicle-based controlis greatly simplified and doe snot need to include a memory function.The only requirement of the control vehicle-based control is that it iscapable of encoding data signals.

As disclosed in commonly assigned U.S. Pat. No. 5,798,575, issued to, byDesmond J. O'Farrell, Roger L. Veldman and Kenneth Schofield for aVEHICLE MIRROR DIGITAL NETWORK AND DYNAMICALLY INTERACTIVE MIRRORSSYSTEM, the disclosure of which is hereby incorporated herein byreference, vehicles are increasingly being equipped with serial datacommunication networks. Such networks include a bidirectional serialmultiplex communication link over a bus among a plurality of controlmodules, each containing a microprocessor or microcomputer. While suchserial data communication network could be utilized to provide acommunication link between the central processor in each of the mirrorassemblies, the protocol of the system provides that higher prioritymessages are communicated without delay while lower priority messagesawait communication of higher priority messages. Becausemirror-positioning messages would be considered lower priority messages,the serial data communication network may often introduce delays inpositioning of the reflective elements. Furthermore, the serial datacommunication networks are relatively complicated with strict protocoldefinitions and rigorous hardware requirements.

It would be desirable to provide a vehicle memory mirror system whichwould incorporate the data processing functions, such as memory storageof multiple mirror positions and the like, in a central control remotefrom at least one of the mirror assemblies while utilizing alow-wire-count interface between the central control and the mirrorassembly.

It would be desirable to provide two or more speeds of operation of amirror-positioning system. When the user is manually positioning themirror, it is desirable to move the mirror at a relatively slow rate inorder to avoid overshoot of the desired setting under the control of theoperator. However, when the mirror is being repositioned to a fixedsetting by the processor, it is desirable for the mirror to move at afaster rate. This is particularly desirable because memory mirrors alsoinclude a downward tilt setting which is a permanent setting invokedwhenever the vehicle is placed in reverse gear. This rotates the mirrorsdownwardly in order to provide a back-up aid to the driver who istypically interested in the area around the vehicle, rather than in thedistance behind the vehicle, when making difficult parking maneuvers andthe like. In order to be useful, it is desirable that the mirrors switchto the downward tilt position immediately upon the vehicle being placedin reverse gear in order to provide immediate assistance to theoperator.

SUMMARY OF THE INVENTION

According to an aspect of the invention, a vehicle memory mirror systemincludes a vehicle mirror assembly and a control module. The vehiclemirror assembly includes a reflective element, a motor for positioningthe reflective element about an axis, a monitor for monitoring theposition of the reflective element with respect to the axis, and amirror-based control operatively connected with the motor and themonitor in order to position the reflective element at a particularposition with respect to the axis. The control module is interconnectedwith the mirror-based control by an analog interface. The control moduleincludes a processor for providing analog signals on the analoginterface indicative of a desired position of the reflective elementwith respect to the axis. The mirror-based control includes apositioning controller circuit which compares analog interface. Thecontrol module is interconnected with the mirror-based control by ananalog interface. The control module includes a processor for providinganalog signals on the analog interface indicative of a desired positionof the reflective element with respect to the axis. The mirror-basedcontrol includes a positioning controller circuit which compares analogsignals on the analog interface with a signal produced by the monitor inorder to generate signals to operate the motor and thereby position thereflective element at the desired position. The vehicle mirror assemblyincludes at least one accessory. The mirror-based control either decodesanalog signals on the analog interface or encodes analog signals on theanalog interface, or both, in order to selectively operate the at leastone accessory. Examples of such mirror-based accessories include a turnsignal light, a stop signal light, a heater, a security light, a garagedoor opener, a power-fold mechanism, and the like.

Preferably, the positioning controller is a servo-controller circuit.The use of a servo-controller circuit provides a reliable analog circuitwhich is capable of responding to the analog signals formatted on theanalog interface in order to reliably position the reflective element atits desired final position. Advantageously, the servo-controller circuitcan be implemented in an application-specific-integrated-circuit forlow-cost, high-volume production. Alternatively, other forms ofpositioning controllers may be used.

According to another aspect of the invention, a vehicle memory mirrorsystem includes a vehicle mirror assembly and a control module. Thevehicle mirror assembly includes a reflective element, a motor forpositioning the reflective element upon an axis, a monitor formonitoring the position of the reflective element with respect to theaxis, and a mirror-based control operatively connected with the motorand the monitor in order to position the reflective element at aparticular position with respect to the axis. The control module isinterconnected with the mirror-based control by an interface. Thecontrol module includes a processor for providing analog signals on theinterface indicative of a desired position of the reflective elementwith respect to the axis. The processor controls the speed at which thereflective element moves toward a terminal position by formattingsignals which each represent an incremental movement of the reflectiveelement with respect to the axis. In this manner, should the processorwish to move the reflective element to a final position at a high rateof speed, the processor formats signals representing the final positionof the reflective element or large incremental movement signals. Thevehicle-based control will then respond by moving the reflective elementat a speed limited only by the hardware of the vehicle mirror assembly.If, however, the control module intends to move the reflective elementat a slower speed, the processor formats a series of analog signals,each of which represents smaller incremental movement of the reflectiveelement. In this manner, the frequency with which the incremental movecommands are issued and the amount of movement represented by eachcommand allows the control module to regulate the speed of movement ofthe reflective element. In this manner, the reflective element can bemoved to its final position at a high rate of speed, for example, whenit is being positioned from a retrieved memory setting. The controlmodule can move the reflective element at a slower rate of speed, forexample, in response to commands manually entered by the driver, inorder to avoid overshoot.

According to yet another aspect of the invention, a vehicle memorymirror system includes first and second vehicle mirror assemblies. Eachassembly includes a reflective element, a motor for positioning thereflective element about an axis, a monitor for monitoring the positionof the reflective element with respect to the axis and a mirror-basedcontrol operatively connected with the motor and the monitor in order toposition the reflective element at a particular position with respect tothe axis. One of the mirror-based controls includes a computer andmemory for storing preselected positions of the reflective elements ofboth of the mirror assemblies. The other mirror-based control isinterconnected with the one mirror-based control by an interface. Theother mirror-based control responds to signals output to the interfaceby the one mirror-based control indicative of a desired position of thereflective element associated with the other mirror-based control and asignal produced by the associated monitor. The other mirror-basedcontrol operates the associated motor in order to position theassociated reflective element to the desired position. Thisconfiguration provides a vehicle mirror network which is exceptionallyeffective and economical.

These and other objects, advantages, and features of this invention willbecome apparent upon review of the following specification inconjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of a vehicle incorporating a memory mirrorsystem according to the invention;

FIG. 2 is a block diagram of a memory mirror system according to theinvention;

FIG. 3 is a diagram illustrating signals used in positioning a mirrorelement according to the invention;

FIG. 4 is a more detailed block diagram of the mirror-based control inFIG. 2;

FIG. 5 is a block diagram of the mirror-based control in FIG. 4;

FIG. 6 is an electrical schematic diagram of the mirror-based control inFIG. 5;

FIG. 7 is a flowchart of a reflective element-positioning routine;

FIG. 8 is the same view as FIG. 2 of an alternative embodiment;

FIG. 9 is an electrical schematic diagram of the mirror-based control inFIG. 8;

FIG. 10 is a block diagram of the mirror-based control in FIG. 9; and

FIG. 11 is the same view as FIG. 2 of another alternative embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now specifically to the drawings, and the illustrativeembodiments depicted therein, a vehicle 10 is illustrated as beingequipped with a vehicle memory mirror system 12 including at least oneexterior mirror 14 and an interior rearview mirror 16 (FIG. 1). Memorymirror system 12 includes an electronic control system 18 made up of amirror-based control module 20 in each exterior rearview mirror 14 and acontrol module 22 which is interconnected with each mirror-based controlmodule 20 by an analog interface 24 (FIGS. 2-6). Mirror-based controlmodule 20 may be positioned within the mirror housing, or head, of theassociated mirror, or may be positioned in the mirror support base.Control module 22 may be located in the vehicle door under the dash, orthe like. Control module 22 may be associated with other vehicle controlfunctions such as seat position control, or the like.

Control module 22 includes a processor 23 which produces analog signalson each analog interface 24 indicative of a desired position of areflective element 26 in respect to an axis of rotation. The desiredposition may be a final position or an intermediate position for thereflective element. However, control module 22 puts out an analog signalon analog interface 24 for each desired movement of the reflectiveelement. As is conventional, reflective element 26 is positioned aboutan axis by a motor 28. A monitoring device, such as a potentiometer 30,is mechanically coupled to reflective element 26 and produces an outputsignal at 32 indicative of the position of the reflective element 26about the axis of rotation. As is also conventional, reflective element26 is positioned about two generally perpendicular axes by a pair ofmotors 28. A pair of potentiometers 30 monitor the position ofreflective element 26 about the two axes of rotation.

In the illustrated embodiment, control module 22 encodes pulse-codedsignals on each analog interface 24 indicative of the desired positionof the reflective element. The reflective element could be anelectro-optic device, such as an electrochromic mirror, or could be aconventional reflective element, such as a chrome reflective element.The pulse-coded signals have a selectable pulse width, each pulse widthrepresentative of a particular position of the reflective element.Because there are two motors 28 for each mirror assembly, control module22 typically encodes two series of pulses on analog interface 24, oneseries of pulses for each of the motors. The two pulse streams may betime-multiplexed on a single-channel analog interface or may be providedin parallel on a dual-channel analog interface. Other analog encodingtechniques are possible. For example, a desired position of thereflective element can be encoded by selecting a particular DC voltageamplitude. The amplitude can be of one polarity or could alternatepolarities to indicate different positional ranges. Likewise, the DCanalog voltage could be supplied to the two motors over a two-channelanalog interface 24 or time division-multiplexed on a single-channelanalog interface.

Control module 22 receives a first set of input signals from a mirrorposition switch assembly 34 and a second set of inputs from a memory setswitch assembly 36. Processor 23 responds to movement of mirror positionswitch 34 by encoding analog signals on analog interface 24representative of inputs entered by the user in the mirror positionswitch. In order to reduce the number of wire interconnections and otherhardware, mirror position switch 34 is used to selectively position bothexterior mirrors 14 with a toggle switch used to designate which of themirrors is being positioned. Mirror position switch 34 may be ajoystick, a switch pod, or similar known input device. Memory set switch36 is operable by the user in order to set memory positions for two ormore vehicle drivers and retrieve memory positions for two or moredrivers. When the operator uses memory set switch assembly 36 to store amirror position, processor 23 stores, in a memory 25, positions ofmotors 28 corresponding to the last commands issued on analog interface24. The assumption is that the mirror-based control module 20 operatedthe motors 28 to the commanded position. When the user retrieves one ofthe memory settings using memory set switch assembly 36, processor 23retrieves the positional settings from memory 25 and encodes analogsignals on analog interface 24 in order to operate motors 28 to positionthe reflective element 26 to the retrieved setting. In addition todriver retrievable positions, memory 25 may contain an additionalsetting in which each reflective element 26 is rotated about ahorizontal direction to a predetermined position such as a fullydownward tilt position. When the vehicle is placed in reverse gear,processor 23 retrieves the downward tilt position and encodes theposition on analog interface 24 in order to drive the mirror reflectiveelements to a downward tilt position. This position aids the driver inreversing the vehicle. In addition, processor 23 may respond to otherinputs, such as one received from a keyless entry system in order toretrieve a mirror setting from memory 25 corresponding to the driverusing that particular keyless entry transmitter. This avoids thenecessity of each driver needing to manipulate memory set switchassembly 36 when that driver uses vehicle 10.

Position controller 40 receives inputs from analog interface 24 andproduces outputs 42 which are supplied to a motor driver 44. Motordriver 44 buffers the signals received from outputs 42 and suppliessufficient electrical energy on its outputs 46 in order to rotate motors28. Preferably, position controller 40 includes a servo-controllercircuit 60 which compares analog signals on analog interface 24, if morethan one series of pulses are multiplexed on interface 24, with signalsproduced by potentiometer 30 in order to operate motors 28 to positionthe reflective element at a desired position. Servo-controller circuit60 may include a pulse decoder 62 in order to decode pulses received onanalog interface 24, if more than one series of pulses are multiplexedon interface 24, and servo amplifier circuit 66 which drives the motorto a position selected by control module 22. If a two-channel analoginterface 24 is used, pulse decoder 62 may be eliminated.Servo-amplifier circuit 66 is made up of a pulse comparator 68 whichreceives a first input from analog interface 24 and a second input 32′from potentiometer 30. Input 32′ is provided to a mono-stablemulti-vibrator 70 to convert the voltage level on input 32′ to a pulsesupplied to pulse comparator 68. Pulse comparator 68 compares the widthof the two input pulses and sets a directional flip-flop 72 to anappropriate output state dependent upon the relative widths of thepulses. Pulse comparator 68 also produces on an output 73 an error pulsehaving a width equal to the difference in widths of the pulses suppliedto its inputs. The outputs of flip-flop 72 are gated by a Schmitttrigger 74 and supplied as an input to motor drive 44′. The duration ofthe gate is a function of the width of the error pulse which is producedby pulse comparator 68 on output 73 and processed by pulse stretcher 76.In this manner, servo-amplifier circuit 66 operates motor 28 until thefeedback received from monitor 30 is equal to the position selected onanalog input 24. In the embodiment illustrated in FIGS. 5 and 6,servo-amplifier circuit 66 is made up of a pair of commerciallyavailable circuits 78 marketed by Ideal Semiconductor under Model No.NE544.

With reference to FIG. 3, control module 22 produces a series of pulsesP on an analog interface, each having a width representative of adesired position of reflective element 26 about one axis. Multivibrator70 produces a series of pulses F, each of which has a width that isproportional to the voltage level developed by potentiometer 30. Hence,the width of pulses F is an indication of the position of reflectiveelement 26. A series of error pulses E are produced at output 73 of apulse comparator. The width of pulses E and the relative widths ofpulses P and F determine the duration and polarity of the energizingpower supplied to motor 28 by motor driver 44. It can be seen in FIG. 3that, as the motor is actuated in response to error pulses E, the widthof pulses F approaches the width of pulses P and the width of errorpulses E diminishes to substantially zero. Control module 22 producespulses for a period of time designed to represent the time it would takethe reflective element to travel from one extent to the other. In theillustrated embodiment, that period of time is approximately five (5)seconds.

In an alternative embodiment, an electronic control system 18′ includesa control module 22, which may be the same control module utilized withelectronic control system 18, and a mirror-based control module 20′(FIGS. 8-10). Each mirror-based control module 20′ includes amicroprocessor 40 which receives inputs from analog interface 24 andproduces outputs 42 which are supplied to a motor driver 44. Motordriver 44 buffers the signals received from microprocessor outputs 42and supplies sufficient electrical energy on its outputs 46 in order torotate motors 28. Analog interface 24 is supplied to an interrupt timerinput 48. This advantageously provides microprocessor 40 with theability to measure the width of each pulse on analog interface 24 inorder to decode the corresponding desired mirror position. Additionally,as an interrupt, input 48 allows microprocessor 40 to “go to sleep” in avery low energy consumption mode when commands are not being received onanalog interface 24. However, when a command is encoded by controlmodule 22, the signal interrupts microprocessor 40 and places themicroprocessor in an active mode. In this manner, electronic controlsystem 18′ can be responsive even when the vehicle is in an OFF-ignitionstate without a large constant drain on the electrical system. Thisallows the driver to position the mirrors prior to starting the vehicle.

In the illustrated embodiment, microprocessor 40 is commerciallyavailable and marketed by Toshiba under Model No. TMP87C408.Microprocessor 40 receives analog signals on two lines designated PULSEONE and PULSE TWO and receives two potentiometer output signalsdesignated POT ONE and POT TWO. Outputs 42 of motor driver 44 aresupplied as positive and negative inputs designated M1⁺, M1⁻, M2⁺ andM2⁻ to the two motors 28. By controlling the amplitude and polarity ofthe signals applied to the outputs 46 of motor driver 44, microprocessor40 is able to drive each motor 28 in both directions.

In addition to performing the memory mirror functions of memory mirrorsystem 12, electronic control system 18′ is capable of operating variousaccessories which may be provided with exterior mirror 14 (FIG. 10). Forexample, as is disclosed in commonly assigned U.S. Pat. No. 5,798,575issued to Desmond J. O'Farrell, Roger L. Veldman and Kenneth Schofieldfor a VEHICLE MIRROR DIGITAL NETWORK AND DYNAMICALLY INTERACTIVE MIRRORSYSTEM, the disclosure of which is hereby incorporated herein byreference, such accessory devices may include a turn or stop signal 52,a heater 56, a security light 50, a garage door opener 54 or apower-fold mechanism 55. Control module 22 can selectively operate anyof such accessories by encoding an analog signal which does not fallwithin the range of analog signals corresponding to desired positions ofreflective elements 26. In this manner, microprocessor 40 is capable ofdecoding such analog signal, determining the device to be controlled andeither activating or deactivating the device as appropriate. In additionto operating accessories, such as security light 50, turn/stop signal52, garage door opener 54, and heater 56, under the command of controlmodule 22, electronic control system 18′ may additionally receive inputsfrom various input devices illustrated in FIG. 5, such as animage-capture device 80, a heading sensor or compass 82, an intrusiondetection circuit 84, an intelligent vehicle highway system (1VHS)transceiver 86, a global positioning system (GPS) receiver 88, a keylessentry receiver 90, a blind spot detector 92, an electro-optical element94, one or more light sensors 96, an outside temperature sensor 98, andthe like. Microcomputer 40 may then encode analog signals on a secondanalog interface 58 and supply such signals to control module 22 usingthe techniques described herein.

Electronic control systems 18, 18′ are capable of controlling the speedof operation of each servo motor 28 utilizing a speed control routine 80(FIG. 7). When it is determined at 82 that control module 22 must send amove command to move motor 28, it is determined at 84 whether the movecommand is one resulting from manual positioning by the operator. If so,then processor 23 produces a series of move commands, each representingan incremental movement of the reflective element that is less than thefinal destination desired. These move commands are generated andformatted on an interface, such as analog interface 24, at a rate thatprovides controlled movement of the reflective element, namely at a ratethat is less than the rate motor 28 is capable of moving the reflectiveelement. This is a function of the amount of movement produced by eachincremental move command as well as the frequency with which the widthof the move commands is modified, as would be understood by thoseskilled in the art. If it is determined at 84 that the move command doesnot result from manual positioning by the user, then processor 23formats a series of move commands at 88 which represents the finaldestination of the reflective element. Thereby, the highest operationalspeed of motor 28 determine the speed at which the reflective element ismoved to its final destination. In this manner, when the move command isinitiated as a result of retrieving a final destination from memory, thereflective element is moved at a faster rate, whereas if the movecommand is a result of manual operation by the operator, the reflectiveelement is moved at a slower rate in order to avoid overshoot.Alternatively, rather than sending a series of pulses of uniform widthequivalent to a final destination to a reposition the reflective elementat a faster rate, processor 23 may send incremental move commands which,because of their frequency and amount of incremental movement, result ina faster rate of movement than the incremental move commands formattedat 86. This principle can be applied to memory mirror systems havinginterface between a vehicle module and a mirror-based control that isdigital, analog, or direct wired.

In an embodiment illustrated in FIG. 11, an electronic control system18″ includes a vehicle module 190 which receives input from a memory setswitch and has an interface 196 with a mirror-based control module 192.Vehicle module 190 is preferably in the vehicle door under the dash, orthe like. Mirror-based control module 192 is positioned in one of theexterior mirrors 14. Interface 196 may be an analog or digital interfaceor direct wired, and is for the primary purpose of passing controlsignals between modules 190 and 192 including actuation of the memoryset switch to either store a particular mirror position or to retrieveone of several stored mirror positions or an indication that the vehiclehas been placed in reverse gear. Mirror-based control module 192receives input directly from mirror position switch 34 indicative of thevehicle operator's desire to manually reposition the reflective element.Mirror-based control module 192 includes a microcomputer 193 whichperforms the function of positioning the associated reflective elementand storing positions of the reflective elements for both mirrors 14,14. In this manner, the memory function for both reflective elements iscarried out by positioning and control module 192.

Positioning and control module 192, positioned in one of the mirrorassemblies 14, 14, is interfaced with a mirror-based positioning modulepositioned in the other of the mirror assemblies 14, 14 by an interface198. Interface 198 may be an analog or digital interface or hard wired.This configuration allows positioning and control module 192 to storeand retrieve positions of the reflective elements associated with bothmirror assemblies 14, 14 and control the positioning of both reflectiveelements, all in response to command inputs from vehicle module 190 andthe mirror position switch. This may be accomplished by including amicroprocessor only with position and control module 192 or also withpositioning module 194. Alternatively, positioning module 194 mayinclude a servo-controller. Positioning module 194 could alternativelybe a conventional memory mirror assembly hardwired at 198 to positionand control module 192.

Thus, it is seen that the present invention provides a system which iscapable of reliable memory mirror positioning in a way which avoids thecomplexity of known digital busy systems and protocols. However, thebenefits of reduced wire count and reliable operation are achieved.Furthermore, a system, according to the invention, is capable ofoperating additional electrical accessories which may be associated withthe exterior mirror. The system is adapted for use in multiple vehiclelines without the requirement for modification of the protocol for eachparticular vehicle line.

Although the invention is illustrated for use in positioning exteriormirrors, it has application for any place on a vehicle where it isdesired to operate a motor in order to position a device. Other examplesinclude vehicle seat positioning, antenna extension, and the like. Thiscan be accomplished in a reliable manner with requiring only a singleelectrical conductor to each of the remote devices.

Changes and modifications in the specifically described embodiments canbe carried out without departing from the principles of the invention,which is intended to be limited only by the scope of the appendedclaims, as interpreted according to the principles of patent lawincluding the Doctrine of Equivalents.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. A vehicular rearviewmirror system for a vehicle having a reverse gear, said mirror systemcomprising: a first rearview mirror assembly and a second rearviewmirror assembly; each of said first and second rearview mirrorassemblies including a housing and a support for attaching said assemblyto a vehicle; each of said first and second rearview mirror assembliesincluding a reflective element and an actuator for positioning saidreflective element about an axis; each of said first and second rearviewmirror assemblies including a control for operating said actuator; saidfirst rearview mirror assembly including a processor adapted todetermine a position for the reflective element of said first rearviewmirror assembly, the position of said reflective element of said firstrearview mirror assembly determined by one of (i) retrieval of one ofseveral positions stored in a memory at said first rearview mirrorassembly and (ii) an indication to said processor of said first rearviewmirror assembly that the vehicle has been placed in reverse gear; saidprocessor of said first rearview mirror assembly further adapted todetermine a position for the reflective element of said second rearviewmirror assembly, said position for the reflective element of said secondrearview mirror assembly also determined by one of (i) retrieval of oneof several positions stored in a memory at said first rearview mirrorassembly and (ii) an indication to said processor of said first rearviewmirror assembly that the vehicle has been placed in reverse gear; andwherein said position for the reflective element of said second rearviewmirror assembly is communicated from said first rearview mirror assemblyby an interface, said interface comprising one of an analog interface, adigital interface and a direct-wired interface.
 2. The vehicularrearview mirror system of claim 1 wherein at least one of the severalpositions is stored in response to actuation of a memory set switch. 3.The vehicular rearview mirror system of claim 1 wherein said first andsecond rearview mirror assemblies are selected from the group consistingof an interior rearview mirror assembly, a driver-side exterior rearviewmirror assembly and a passenger-side exterior rearview mirror assembly.4. The vehicular rearview mirror system of claim 3 wherein one of saidfirst and second rearview mirror assemblies comprises said driver-sideexterior rearview mirror assembly and the other of said first and secondrearview mirror assemblies comprises said passenger-side exteriorrearview mirror assembly.
 5. The vehicular rearview mirror system inclaim 3 wherein one of said first and second rearview mirror assembliescomprises said interior rearview mirror assembly and the other of saidfirst and second rearview mirror assemblies comprises said driver-sideexterior rearview mirror assembly.
 6. The vehicular rearview mirrorsystem in claim 3 wherein one of said first and second rearview mirrorassemblies comprises said interior rearview mirror assembly and theother of said first and second rearview mirror assemblies comprises saidpassenger-side exterior rearview mirror assembly.
 7. The vehicularrearview mirror system in claim 1 wherein said first rearview mirrorassembly comprises an interior rearview mirror assembly and said secondrearview mirror assembly comprises one of a driver-side exteriorrearview mirror assembly and a passenger-side exterior rearview mirrorassembly.
 8. The vehicular rearview system of claim 1 wherein each ofsaid first and second rearview mirror assemblies includes a positionmonitor for monitoring the position of said respective reflectiveelement about said respective axis, wherein said respective controlcompares a position of said respective reflective element about saidrespective axis with a position determined for that reflective element.9. The vehicular rearview system of claim 1 wherein said control of atleast one of said first and second rearview mirror assemblies comprisesa servo-controller circuit.
 10. The vehicular rearview system of claim 1wherein at least one of said first and second rearview mirror assembliesincludes at least one accessory and wherein said control of said atleast one of said first and second rearview mirror assemblies controlssaid at least one accessory.
 11. The vehicular rearview system of claim10 wherein said at least one accessory comprises a turn signal.
 12. Thevehicular rearview system of claim 11 wherein said control of said atleast one of said first and second rearview mirror assemblies providesan output to operate said turn signal.
 13. The vehicular rearview systemof claim 10 wherein said at least one accessory comprises a stop signal.14. The vehicular rearview system of claim 13 wherein said control ofsaid at least one of said first and second rearview mirror assembliesprovides an output to operate said stop signal.
 15. The vehicularrearview system of claim 10 wherein said at least one accessorycomprises a security light.
 16. The vehicular rearview system of claim15 wherein said control of said at least one of said first and secondrearview mirror assemblies provides an output to operate said securitylight.
 17. The vehicular rearview system of claim 15 wherein saidcontrol of said at least one of said first and second rearview mirrorassemblies receives an input from a keyless entry receiver system toactuate said security light.
 18. The vehicular rearview system of claim10 wherein said at least one accessory comprises a power-fold mechanism.19. The vehicular rearview system of claim 18 wherein said control ofsaid at least one of said first and second rearview mirror assembliesprovides an output to operate said power-fold mechanism.
 20. Thevehicular rearview system of claim 10, wherein said at least oneaccessory comprises an electro-optical element.
 21. The vehicularrearview system of claim 20 wherein said control of said at least one ofsaid first and second rearview mirror assemblies provides an output tooperate said electro-optical element.
 22. The vehicular rearview systemof claim 20 wherein said reflective element of at least one of saidfirst and second rearview mirror assemblies comprises saidelectro-optical element and wherein said control of said at least one ofsaid first and second rearview mirror assemblies provides an output tooperate said electro-optical reflective element.
 23. The vehicularrearview system of claim 22 wherein said electro-optical elementcomprises an electrochromic mirror.
 24. The vehicular exterior rearviewmirror system of claim 1 wherein said control of at least one of saidfirst and second rearview mirror assemblies controls the speed at whichthe associated said reflective element moves toward a particularposition.
 25. The vehicular exterior rearview mirror system of claim 24wherein said control of at least one of said first and second rearviewmirror assemblies initially moves the associated said reflective elementtoward said particular position at a first speed and subsequently movesthe associated said reflective element toward said particular positionat a second speed.
 26. The vehicular exterior rearview mirror system ofclaim 25 wherein said second speed is less than said first speed. 27.The vehicular rearview system of claim 1 wherein said control of saidfirst rearview mirror assembly comprises a microprocessor.
 28. Thevehicular rearview system of claim 1 wherein said control of said firstrearview mirror assembly comprises said processor.
 29. The vehicularrearview system of claim 28 wherein said processor comprises amicroprocessor.
 30. A vehicular rearview mirror system for a vehiclehaving a reverse gear, said mirror system comprising: a first rearviewmirror assembly and a second rearview mirror assembly; each of saidfirst and second rearview mirror assemblies including a housing and asupport for attaching said assembly to a vehicle; each of said first andsecond rearview mirror assemblies including a reflective element and anactuator for positioning said reflective element about an axis; each ofsaid first and second rearview mirror assemblies including amirror-based control for operating the respective said actuator; saidmirror-based control of one of said first and second rearview mirrorassemblies comprising a microcomputer and memory for storing severalpositions of said reflective elements of said first and second rearviewmirror assemblies; said mirror-based controls of said first and secondrearview mirror assemblies connected by an interface wherein saidmirror-based control of the other of said first and second rearviewmirror assemblies responds to a signal output to said interface by saidmirror-based control of said one of said first and second rearviewmirror assemblies indicative of a desired position of said reflectiveelement of said other of said first and second rearview mirrorassemblies.
 31. The vehicular rearview mirror system of claim 30 whereinsaid interface comprises one of an analog interface, a digital interfaceand a direct-wired interface.
 32. The vehicular rearview mirror systemof claim 30 wherein at least one of the several positions is stored inresponse to actuation of a memory set switch.
 33. The vehicular rearviewmirror system of claim 30 wherein said first and second rearview mirrorassemblies are selected from the group consisting of an interiorrearview mirrors. assembly, a driver-side exterior rearview mirrorassembly and a passenger-side exterior rearview mirror assembly.
 34. Thevehicular rearview mirror system of claim 33 wherein one of said firstand second rearview mirror assemblies comprises said driver-sideexterior rearview mirror assembly and the other of said first and secondrearview mirror assemblies comprises said passenger-side exteriorrearview mirror assembly.
 35. The vehicular rearview mirror system inclaim 33 wherein one of said first and second rearview mirror assembliescomprises said interior rearview mirror assembly and the other of saidfirst and second rearview mirror assemblies comprises said driver-sideexterior rearview mirror assembly.
 36. The vehicular rearview mirrorsystem in claim 33 wherein one of said first and second rearview mirrorassemblies comprises said interior rearview mirror assembly and theother of said first and second rearview mirror assemblies comprises saidpassenger-side exterior rearview mirror assembly.
 37. The vehicularrearview mirror system in claim 30 wherein said first rearview mirrorassembly comprises an interior rearview mirror assembly and said secondrearview mirror assembly comprises one of a driver-side exteriorrearview mirror assembly and a passenger-side exterior rearview mirrorassembly.
 38. The vehicular rearview system of claim 30 wherein each ofsaid first and second rearview mirror assemblies includes a positionmonitor for monitoring the position of said respective reflectiveelement about said respective axis, wherein said respective mirror-basedcontrol compares a position of said respective reflective element aboutsaid respective axis with a position determined for that reflectiveelement.
 39. The vehicular rearview system of claim 30 wherein at leastone of said mirror-based controls comprises a servo-controller circuit.40. The vehicular rearview system of claim 30 wherein at least one ofsaid first and second rearview mirror assemblies includes at least oneaccessory and wherein said mirror-based control of said at least one ofsaid first and second rearview mirror assemblies controls said at leastone accessory.
 41. The vehicular rearview system of claim 40 whereinsaid at least one accessory comprises a turn signal.
 42. The vehicularrearview system of claim 41 wherein said mirror-based control of said atleast one of said first and second rearview mirror assemblies providesan output to operate said turn signal.
 43. The vehicular rearview systemof claim 40 wherein said at least one accessory comprises a stop signal.44. The vehicular rearview system of claim 43 wherein said mirror-basedcontrol of said at least one of said first and second rearview mirrorassemblies provides an output to operate said stop signal.
 45. Thevehicular rearview system of claim 40 wherein said at least oneaccessory comprises a security light.
 46. The vehicular rearview systemof claim 45 wherein said mirror-based control of said at least one ofsaid first and second rearview mirror assemblies provides an output tooperate said security light.
 47. The vehicular rearview system of claim45 wherein said mirror-based control of said at least one of said firstand second rearview mirror assemblies receives an input from a keylessentry receiver system to actuate said security light.
 48. The vehicularrearview system of claim 40 wherein said at least one accessorycomprises a power-fold mechanism.
 49. The vehicular rearview system ofclaim 48 wherein said mirror-based control of said at least one of saidfirst and second rearview mirror assemblies provides an output tooperate said power-fold mechanism.
 50. The vehicular rearview system ofclaim 48 wherein said at least one accessory comprises anelectro-optical element.
 51. The vehicular rearview system of claim 50wherein said mirror-based control of said at least one of said first andsecond rearview mirror assemblies provides an output to operate saidelectro-optical element.
 52. The vehicular rearview system of claim 50wherein said reflective element of said at least one of said first andsecond rearview mirror assemblies comprises said electro-optical elementand wherein said mirror-based control of said at least one of said firstand second rearview mirror assemblies provides an output to operate saidelectro-optical reflective element.
 53. The vehicular rearview system ofclaim 50 wherein said electro-optical element comprises anelectrochromic mirror.
 54. The vehicular rearview mirror system of claim30 wherein the position of said reflective element of said firstrearview mirror assembly is determined by one of (i) retrieval of one ofthe several positions stored in said memory and (ii) an indication tosaid microcomputer that the vehicle has been placed in reverse gear. 55.The vehicular rearview mirror system of claim 54 wherein the positionfor the reflective element of said second rearview mirror assembly isdetermined by one of (i) retrieval of one of several positions stored insaid memory and (ii) an indication to said microcomputer that thevehicle has been placed in reverse gear.
 56. A vehicular rearview mirrorsystem for a vehicle having a reverse gear, said mirror systemcomprising: a first rearview mirror assembly and a second rearviewmirror assembly; each of said first and second rearview mirrorassemblies including a housing and a support for attaching said assemblyto a vehicle; each of said first and second rearview mirror assembliesincluding a reflective element and an actuator for positioning saidreflective element about an axis; each of said first and second rearviewmirror assemblies including a control for operating said actuator; saidfirst rearview mirror assembly including a processor adapted todetermine a position for the reflective element of said first rearviewmirror assembly, the position of said reflective element of said firstrearview mirror assembly determined by one of (i) retrieval of one ofseveral positions stored in a memory at said first rearview mirrorassembly and (ii) an indication to said processor of said first rearviewmirror assembly that the vehicle has been placed in reverse gear; saidprocessor of said first rearview mirror assembly further adapted todetermine a position for the reflective element of said second rearviewmirror assembly, said position for the reflective element of said secondrearview mirror assembly also determined by one of (i) retrieval of oneof several positions stored in a memory at said first rearview mirrorassembly and (ii) an indication to said processor of said first rearviewmirror assembly that the vehicle has been placed in reverse gear;wherein at least one of said first and second rearview mirror assembliesincludes at least two accessories selected from the group consisting ofa turn signal, a stop signal, a heater, a security light, a power-foldmechanism, an electro-optical element, an intelligent vehicle highwaysystem transceiver, said actuator and a garage door opener; and whereinsaid control of said at least one of said first and second rearviewmirror assemblies controls said at least two accessories.
 57. Thevehicular rearview mirror system of claim 56 wherein at least one ofsaid actuators of said first and second rearview mirror assembliesfurther comprises a monitor for monitoring the position of saidrespective reflective element with respect to said respective axis, saidrespective control operatively connected with said actuator in order toposition said respective reflective element at a particular positionwith respect to said respective axis.
 58. The vehicular rearview mirrorsystem of claim 56 wherein said control of at least one of said firstand second rearview mirror assemblies controls the speed at which theassociated said reflective element moves toward a particular position.59. The vehicular rearview mirror system of claim 58 wherein saidcontrol of at least one of said first and second rearview mirrorassemblies initially moves the associated said reflective element towarda particular position at a first speed and subsequently moves theassociated said reflective element toward said particular position at asecond speed.
 60. The vehicular rearview mirror system of claim 59wherein said second speed is less than said first speed.
 61. Thevehicular rearview mirror system of claim 56 wherein said control ofsaid at least one of said first and second rearview mirror assembliesincludes a drive circuit which supplies electrical energy to said atleast two accessories.
 62. The vehicular rearview mirror system of claim56 wherein said at least two accessories comprise at least one of saidturn signal and said security light.
 63. The vehicular rearview mirrorsystem of claim 62 wherein said control of said at least one of saidfirst and second rearview mirror assemblies provides an output tooperate said at least one of said turn signal and said security light.64. The vehicular rearview mirror system of claim 56 wherein said atleast two accessories comprise at least one of said stop signal and saidturn signal.
 65. The vehicular rearview mirror system of claim 64wherein said control of said at least one of said first and secondrearview mirror assemblies provides an output to operate said at leastone of said stop signal and said turn signal.
 66. The vehicular rearviewmirror system of claim 56 wherein said at least two accessories compriseat least one of said security light and said stop signal.
 67. Thevehicular exterior rearview mirror system of claim 66 wherein saidcontrol of said at least one of said first and second rearview mirrorassemblies provides an output to operate said at least one of saidsecurity light and said stop signal.
 68. The vehicular rearview mirrorsystem of claim 67 wherein said control of said at least one of saidfirst and second rearview mirror assemblies receives an input from akeyless entry receiver system to actuate said security light.
 69. Thevehicular rearview mirror system of claim 56 wherein said at least twoaccessories comprise at least one of said power-fold mechanism and saidactuator.
 70. The vehicular rearview mirror system of claim 69 whereinsaid control of said at least one of said first and second rearviewmirror assemblies provides an output to operate said at least one ofsaid power-fold mechanism and said actuator.
 71. The vehicular rearviewmirror system of claim 56 wherein said at least two accessories compriseat least one of said electro-optical element and said heater.
 72. Thevehicular rearview mirror system of claim 71 wherein said control ofsaid at least one of said first and second rearview mirror assembliesprovides an output to operate said at least one of said electro-opticalelement and said heater.
 73. The vehicular rearview mirror system ofclaim 71 wherein said reflective element comprises said electro-opticalelement and wherein said control provides an output to operate saidelectro-optical reflective element.
 74. The vehicular rearview mirrorsystem of claim 73 wherein said electro-optical element comprises anelectrochromic mirror.
 75. The vehicular rearview mirror system of claim56 wherein said control of said at least one of said first and secondrearview mirror assemblies includes a microprocessor.
 76. The vehicularrearview mirror system of claim 56 wherein the position for thereflective element of said second rearview mirror assembly iscommunicated from said first rearview mirror assembly by an interface.77. The vehicular rearview mirror system of claim 76 wherein saidinterface comprises an interrupt timer input.
 78. The vehicular rearviewmirror system of claim 76 wherein said interface comprises asingle-channel analog interface.
 79. The vehicular rearview mirrorsystem of claim 76 wherein said interface comprises a dual-channelanalog interface.
 80. The vehicular rearview mirror system of claim 76wherein said interface comprises one of an analog interface, a digitalinterface and a direct-wired interface.
 81. The vehicular rearviewmirror system of claim 56 wherein at least one of the several positionsof said first and second rearview mirror assemblies are stored inresponse to actuation of a memory set switch.
 82. The vehicular rearviewmirror system of claim 56 wherein said first and second rearview mirrorassemblies are selected from the group consisting of an interiorrearview mirror assembly, a driver-side exterior rearview mirrorassembly and a passenger-side exterior rearview mirror assembly.
 83. Thevehicular rearview mirror system of claim 82 wherein one of said firstand second rearview mirror assemblies comprises said driver-sideexterior rearview mirror assembly and the other of said first and secondrearview mirror assemblies comprises said passenger-side exteriorrearview mirror assembly.
 84. The vehicular rearview mirror system inclaim 82 wherein one of said first and second rearview mirror assembliescomprise said interior rearview mirror assembly and the other of saidfirst and second rearview mirror assemblies comprises said driver-sideexterior rearview mirror assembly.
 85. The vehicular rearview mirrorsystem in claim 82 wherein one of said first an second rearview mirrorassemblies comprise said interior rearview mirror assembly and the otherof said first and second rearview mirror assemblies comprises saidpassenger-side exterior rearview mirror assembly.
 86. The vehicularrearview mirror system in claim 56 wherein said first rearview mirrorassembly comprises an interior rearview mirror assembly and said secondrearview mirror assembly comprises one of a driver-side exteriorrearview mirror assembly and a passenger-side exterior rearview mirrorassembly.
 87. The vehicular rearview system of claim 56 wherein saidcontrol of at least one of said first an second rearview mirrorassemblies comprises a servo-controller circuit.